The invention relates to an improved method and apparatus for anaesthetizing animals for slaughter using gas by transporting the animals for anaesthetizing trough a gas-filled anaesthetizing space.
It is usual to anaesthetize animals prior to slaughter. Anaesthetizing can take place for instance by means of electric shock of using an anaesthetizing gas. It is known to suffocate animals using CO.sub.2 in a tunnel, bath or lower-lying space (the specific mass of CO.sub.2 is greater than the specific mass of air). The transition area from normal atmospheric conditions to the conditioned anaesthetizing environment is relatively long. This means that the anaesthetizing process begins gradually. A drawback here is that the anaesthetizing process takes a relatively long time, with a larger space thus being required. The animals for slaughter moreover become excited during the initial progress, which has an adverse effect on the final quality of the meat and results in a not very animal-friendly slaughtering process.
The present invention has for its object to provide an apparatus and method with which animals for slaughter can be anaesthetized quickly using gas, wherein the animals become less excited, thus resulting in a better meat quality.
Another advantage of a controlled gas composition in the anaesthetizing of animals for slaughter is that the biochemical process which occurs in the animals is better controlled, which results in a better control and even influencing of the meat quality of the slaughtered animals.
The present invention provides for this purpose a method according to claim 1.
WO-A-94/15469 discloses a method for anaesthetizing animals for slaughter using gas by transporting the animals for anaesthetizing through two adjacent gas-filled anaesthetizing chambers separated by a partition. This partition may be for e.g. a strip curtain, an air curtain, a water curtain or a moving screen. The purpose of the partition is to separate the gas atmospheres in the respective chambers. In each of the chambers a specific gas is introduced through a respective gas feed. Optionally, part of the gas in its first chamber is removed by means of a pipe debouching in the first chamber for recirculating the gas thus removed from the first chamber for recirculation after mixing with the gas fed to the second chamber. This prior art arrangement does not allow a simple yet effective control of the respective gas atmospheres in the two chambers.